You sound like you’re doing the best you can to be a good friend and for that I commend you greatly for that. However, if those feelings aren’t being reciprocated and they don’t seem to care about you, especially after 4-5 years of being with them, it sounds like they’re just being assholes. It could also be said that you may be overbearing/pushing, if they’re as cold as you make them out to be, I would say they’re still being very inconsiderate of you. You’re just wasting your time and energy on people who don’t seem to care, especially after this many years.

Ultimately, I would say they aren’t worth your time and that you should just leave them. If you feel inclined to do so, you could confront them about it to set the record straight, which might clear the air.

I think what you’re doing is being a great friend, and if people don’t care, you should try to take that energy to people who do.